Communication circuitry is typically for communication across a communication interface using a given communication protocol. Data to be communicated under such a communication protocol may be handled in synchronisation with a clock signal, in which case parallel data and clock paths may be established across the communication interface via respective data and clock communication nodes. Data in this context may include control data.
Communication circuitry finds wide use. Circuitry systems are typically made up of circuitry sub-systems which need to communicate with one another. Example circuitry sub-systems include application processors and processing circuits, for example audio application processors which handle audio data. Of course, audio data is merely one example type of data which may need to be communicated within a data processing system. In the context of circuitry having peripheral input/output components such as sensors/transducers, other examples include video, audio, haptics and/or any other sensor/transducer data.
Such communication circuitry may be implemented on ICs (integrated circuits) or other circuitry systems in a host device, which may be considered an electrical or electronic device. Examples include a portable and/or battery powered host device such as a mobile telephone, an audio player, a video player, a PDA, a mobile computing platform such as a laptop computer or tablet and/or a games device.
The number of communication nodes required becomes an issue particularly in communication circuitry designed to support multiple communication protocols. An advanced digital communication circuit (e.g. implemented on an IC chip) for example typically needs to support a multitude of different communication protocols, where an associated apparatus chooses a subset of them (such as only one of them). Thus, in any one application such a circuit may only need to use a single one of its supported communication protocols. In that case, any communication nodes provided for the ultimately unused communication protocol or protocols may be considered redundant.
Taking forward the example of integrated circuitry, communication nodes may be internal to the communication circuitry concerned in which case the number of communication nodes and corresponding communication paths might only impact circuit layout and area. However, such communication nodes may be external nodes of the integrated circuit, corresponding to connection pins or bond pads/solder balls. The continued miniaturisation of ICs has led to decreasing chip size and decreasing chip package ball count. There is therefore pressure to reduce pin count as technology advances. Potential candidates for pin count reduction are control and data pins.
It is desirable to address the above problems, for example the conflict between supporting multiple communication protocols and reducing the number of communication nodes required.